Cervical spinal cord infarction due to impingement of an anomalous right vertebral artery by thoracic osteophyte.

Introduction: Spinal cord infarction in a young, otherwise healthy individual is a rare occurrence. The anterior spinal artery and posterior spinal arteries are the primary contributors to the vascular supply of the cervical supply, and these arteries arise as descending branches of the vertebral arteries. Historically, many cases have demonstrated individual variations in the vertebral arteries, such as differences in dominancy, patency, origin, and insertion. The clinical significance of these variations remains poorly understood.

Case Presentation: We present a patient who sustained a spinal cord infarction at C2-C5 resulting in incomplete quadriplegia. The mechanism of injury was unclear, although the patient reported an awkward jumping motion earlier that day that preceded the onset of upper extremity weakness. After resolution of the acute phase, he was diagnosed with "Man-in-the-Barrel" syndrome. Angiographic evaluation revealed an anomalous non-dominant right vertebral artery with several pathological features: origin at the descending aorta, insertion into the right posterior inferior cerebellar artery, and impingement along its course by an anterior thoracic osteophyte.

Discussion: The vertebral arteries play an important role in the vascular supply of the cervical spine. While vertebral artery pathology such as dissection or occlusion have been documented in rare cases to result in spinal cord infarction, this case illustrates an example of clinically significant sequelae that can occur in the setting of anomalous vertebral arteries even in the absence of occlusion or dissection. Furthermore, to our knowledge this is the first reported case of a spinal cord infarction resulting from osteophytic vertebral artery impingement.